Is your Vortech on a SVT or ZX3 engine? If it's an SVT engine how much clearance to did you have between that and the water pump pulley? Looks like the belt almost touches each other between the 2 pulleys.

According to the calculation I made and from the manual.

The C-2 Procharger with the 2.55" Blower and 5.7" Crank Pulley @ 7200rpm will spin the impeller at 75642.3 rpms. The limit is 80,000. That's 15psi @ 5500rpms on the tach, after which the supercharger can give no more oomph for power.

With a 5.9" Crank Pulley it spins @ 78296.5 rpms. I'm thinking maybe just for track days to use it, and put the 5.7" back on for daily driving.

I'm just trying to squeeze a few more lbs of torque mostly by hopefully increasing boost by maybe 2-5 lbs.

I may be interested in a 5.9 if not perhaps a custom 8.5 to be safe. Also did you upgrade the plastic pulleys on the tensioner and alternator to billet types to help support over spinning?